# Understand different integration results with practically the same input?

GROUPS:
 Hi folks, Im new, so Im not sure this is the right place to drop my question. In[1]: Integrate[Exp[-10 x]/(1 - (9/10) Exp[-10 x])^2, {x, 0, Infinity}] Out[1]: 1 In[2]: Integrate[Exp[-10 x]/(1 - 0.9 Exp[-10 x])^2, {x, 0, Infinity}] Out[2]: 1. - 1.10218*10^-15 i My question is why in the second output I get that if the input is practically the same as In[1] (I just changed (9/10) for 0.9)Thanks.